A Health Risk Assessment of Heavy Metals in Contaminated Vegetables and Soil Irrigated with Wastewater in the Dera Ghazi Khan, Pakistan, Area

Abstract

Abstract Anthropogenic factors like industrialization, urbanization, and agrochemical products causes metal pollution in the food chain. Vegetables produced on polluted soil expose individuals to carcinogenic heavy metals once they ingest them. The study examined the risks of contaminants in vegetables cultivated on soils irrigated through wastewater, their origins, and the consequences to individuals. Through analytical techniques of atomic absorption spectrophotometer, total 164 water samples, topsoil, and vegetables for the concentration level of eight toxic metals (Pb, Cd, Cu, Mn, Fe, Zn, Ni, and Cr) were examined. Heavy metals (Cd, Zn, Fe, Cu, Mn, Cr, Pb, and Ni) in untreated wastewater ranged from 0.405 to 0.501, 0.207 to 0.288, 0.185 to 0.273, 0.565 to 0.883, 0.077 to 0.210, 0.206 to 0.293, 7.750 to 10.080, and 0.189 to 0.293 mg L− 1 respectively. The results showed that heavy metals had accumulated significantly in the soil and transferred to vegetables. Vegetables grown on soil irrigated with untreated wastewater had metal concentrations substantially higher than those grown on freshwater-irrigated soil and were above US-EPA and World Health Organization (WHO) guidelines. ANOVA analysis showed no significant differences between the levels of heavy metals in soil. Pearson's correlation coefficient showed a significant positive association between (Pb-Cr) and (Zn-Cu) for soil data. Eight heavy metals categorized into three cluster for soil and seven cluster for vegetables. Three latent components with eigenvalues greater than 1.0 displayed a positive load of anthropogenic trace metals (Ni and Cu) generated for soil data. Pb and Cd have HRIs of > 1 in all vegetables, and Ni has HRIs > 1 for Raphanus sativus, Brassica oleracea, and Spinacia oleracea. Children and adults exposed to a substantial amount of harmful metals using such vegetables.